quicktime 10.5 catalina does not launch

Good morning musicchefd!

I see that you're having trouble with the QuickTime app because it's no longer opening in macOS Catalina. I'll be happy to help out.

Have you restarted the Mac yet? If not, try that now. If you're still unable to open the QuickTime app, try in safe mode. If you're able to open QuickTime in safe mode, restart normally and then try again: Use safe mode to isolate issues with your Mac - Apple Support. If the issue didn't occur in safe mode, but does occur when restarting the Mac, take a look at that same resource under "If an issue doesn't happen in safe mode" for some reasons why this might be happening.

Keep us updated. Take care. 

Hey musicchefd,

Thanks for reaching back out. Since the issue also occurred in safe mode, try creating a test user account next to see if QuickTime launches normally. Creating a test user account can help determine if the issue is caused by third-party software: How to test an issue in another user account on your Mac. There's steps to take further in that resource, depending if the issue happens in the test user account or not but you can also let us know the results.

Cheers!